M/T

DTC P0325 - KNOCK SENSOR CIRCUIT MALFUNCTION

DTC DETECTING CONDITION:
- Immediately at fault recognition

TROUBLE SYMPTOM:
- Poor driving performance
- Knocking occurs.

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.

Wiring Diagram:

WIRING DIAGRAM

10AC1: CHECK HARNESS BETWEEN KNOCK SENSOR AND ECM CONNECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connector from ECM.

Connector & Terminal - [(B136) No.4 - Chassis Ground]:

3. Measure resistance between ECM harness connector and chassis ground.

CHECK: Is the resistance more than 700 K.Ohms?

YES: Go to step 10AC3.

NO: Go to step 10AC2.

10AC2: CHECK HARNESS BETWEEN KNOCK SENSOR AND ECM CONNECTOR.

Connector & Terminal - [(B136) No.4 - Chassis Ground]:

Measure resistance of harness between ECM connector and chassis ground.

CHECK: Is the resistance less than 400 K.Ohms?

YES: Go to step 10AC5.

NO: Go to step 10AC6.

10AC3: CHECK KNOCK SENSOR.
1. Disconnect connector from knock sensor.

Terminals - [No.2 - Engine Ground]:

2. Measure resistance between knock sensor connector terminal and engine ground.

CHECK: Is the resistance more than 700 K.Ohms?

YES: Go to step 10AC4.

NO: Repair harness and connector.

NOTE:
In this case, repair the following:
- Open circuit in harness between knock sensor and ECM connector
- Poor contact in knock sensor connector
- Poor contact in coupling connector (B21)

10AC4: CHECK CONDITION OF KNOCK SENSOR INSTALLATION.

CHECK: Is the knock sensor installation bolt tightened securely?

YES: Replace knock sensor.

NO: Tighten knock sensor installation bolt securely.

10AC5: CHECK KNOCK SENSOR.

1. Disconnect connector from knock sensor.

Terminal - [No.2 - Engine Ground]:

2. Measure resistance between knock sensor connector terminal and engine ground.

CHECK: Is the resistance less than 400 K.Ohms?

YES: Replace knock sensor.

NO: Repair ground short circuit in harness between knock sensor connector and ECM connector.

NOTE: The harness between both connectors is shielded. Repair short circuit of harness together with shield.

10AC6: CHECK INPUT SIGNAL FOR ECM.

1. Connect connectors to ECM and knock sensor.
2. Turn ignition switch to ON.

Connector & Terminal - [(B136) No.4 - Chassis Ground (-)]:

3. Measure voltage between ECM and chassis ground.

CHECK: Is the voltage more than 2 V? NOTE: In this case, repair the following:
- Poor contact in knock sensor connector
- Poor contact in ECM connector
- Poor contact in coupling connector (B21)

NO: Repair poor contact in ECM connector.